The study seeks to provide support for the hypothesis that anxiety affects progress in labor. Beginning with the last trimester of pregnancy, data are being analyzed for 32 married primigravid women, 20-32 years old with no complicating medical or obstetrical conditions. During pregnancy data was gathered through the use of objectively scored instruments on trait anxiety, anticipation of difficulty in labor, and knowledge of the events of labor. Three interview sessions were also conducted, and the subjects kept a diary and dream record. From these data, measures on 15 additional variables on fears and conflicts have been obtained. During labor objective measures of state anxiety, plasma catecholamine levels of epinephrine and norepinephrine, plasma cortisol levels, and uterine activity were obtained at the beginning of three obstetrically defined phases of labor and after delivery. Variation in cervical dilatation was controlled, and the proportion of the remaining variation in uterine activity which can be accounted for by anxiety, cortisol, and catecholamine levels is being determined. The relationship between anxiety and length of labor, and the predictability of the variables measured in labor from the variables measured prior to labor are also being determined.